Ball type continuously variable transmission/infinitely variable transmission

ABSTRACT

A variable transmission includes an input shaft, a planetary gear set drivingly engaged with a variator comprising, a variator carrier assembly, a first ring assembly, and a second ring assembly; and the output shaft, arranged with various combinations of brakes and clutches to produce transmissions with continuously variable or infinitely variable torque output ratios.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No.14/622,038, filed Feb. 13, 2015, which is a division of U.S. patentapplication Ser. 14/020,593, filed Sep. 6, 2013, now issued as U.S. Pat.No. 8,986,150 on Mar. 24, 2015, which claims the benefit of priority toU.S. Provisional Patent Application No. 61/698,005, filed Sep. 7, 2012and U.S. Provisional Patent Application No. 61/782,924, filed Mar. 14,2013, all of which are incorporated herein by reference in theirentireties.

BACKGROUND OF THE INVENTION

Automatic and manual transmissions are commonly used on automobilevehicles. Those transmissions are becoming more and more complicatedsince the engine speed has to be more precisely controlled to limit thefuel consumption and the emissions of cars. This finer control of theengine speed in usual transmissions can only be done by adding morediscrete step ratio gears and increasing the overall complexity andcost. Consequently, 6-speed manual transmissions then become morefrequently used as are 8 or 9 speed automatic transmissions.

SUMMARY OF THE INVENTION

Provided herein is a variable transmission comprising; a power inputshaft; a planetary gear set mechanically coupled to the power inputshaft, a variator comprising, a variator carrier assembly, a first ringassembly, and a second ring assembly; and various combinations of brakesand clutches.

In any of the embodiments disclosed herein the variable transmission maybe a continuously variable transmission

In some embodiments, the variable transmission comprises a variatorhaving a continuously variable mode, an infinitely variable mode or acombination thereof.

In some embodiments the variable transmission can provide a reversefunction, a standstill function and a low speed function.

In some embodiments, the transition between continuously variabletransmission mode and infinitely variable transmission mode isaccomplished by simultaneously releasing one of the brakes and applyingthe other brake.

In some embodiments, the transition between continuously variabletransmission mode and infinitely variable transmission mode isaccomplished by releasing the clutch and engaging the brake.

In some embodiments, the variator is able to continuously change itstorque ratios in both the continuously variable mode and infinitelyvariable mode to provide the best ratio achievable for the engine tooptimize performance or fuel consumption.

Provided herein is a variable transmission comprising: an input shaft; aplanetary gear set, wherein a carrier of the planetary gear set isdrivingly engaged with the input shaft; a first brake mechanicallycoupled to a ring gear of the planetary gear set; a variator comprisinga variator carrier assembly, a first ring assembly, and a second ringassembly, wherein the variator carrier assembly is mechanically coupledto the ring gear of the planetary gear set; and a second brake ismechanically coupled to a sun gear of the planetary gear set and to thefirst ring assembly of the variator, and wherein the second ringassembly of the variator assembly is drivingly engaged to the output ofthe variable transmission.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode. In some embodiments, whenthe first brake is engaged and the second brake is disengaged, the ringgear of the planetary gear set and the variator carrier assembly areheld fixed, thereby engaging a continuously variable mode. In someembodiments, power passes through the sun gear of the planetary gear setto the first ring assembly when the transmission is in continuouslyvariable mode.

In some embodiments, when the second brake is engaged and the firstbrake is disengaged, the sun gear of the planetary gear set and thefirst ring assembly are held fixed, thereby engaging an infinitelyvariable mode. In some embodiments, power passes through the ring gearof the planetary gear set to variator carrier assembly in the infinitelyvariable mode. In some embodiments, in the infinitely variable mode, thevariator provides a reverse function, a standstill function and a lowspeed function.

In some embodiments, a transition between continuously variable mode andinfinitely variable mode is accomplished by simultaneously releasing oneof the first brake and the second brake while applying the other of thefirst brake and the second brake. In some embodiments, the variatorcontinuously changes its torque ratios in both the continuously variablemode and infinitely variable mode to optimize performance or fuelconsumption. In some embodiments, the variator continuously changes itstorque ratios in both the continuously variable mode and infinitelyvariable mode to achieve an ideal ratio for variable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode provide a gap in rotation speeds of the second ringassembly. In one embodiment, the gap is compensated by engine speedadjustment. In some embodiments, the relationship of rotation speeds ofthe second ring assembly in the continuously variable mode and thesecond ring assembly in the infinitely variable mode, and the rotationspeed of the input shaft from the engine is as shown in FIG. 5.

Provided herein is a variable transmission comprising: an input shaft; aplanetary gear set, wherein a ring gear of the planetary gear set isdrivingly engaged with the input shaft; a variator comprising a variatorcarrier assembly, a first ring assembly, and a second ring assembly; aplanetary gear carrier of the planetary gear set coupled to a firstbrake and to the second ring assembly; and a sun gear of the planetarygear set coupled to a second brake and the variator carrier assembly,and wherein the second ring assembly of the variator is drivinglyengaged to the output of the variable transmission.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the second brake is engaged and the firstbrake is disengaged, the sun gear of the planetary gear set is fixedtogether with the variator carrier assembly to engage a continuouslyvariable mode. In some embodiments, input power passes through the ringgear of the planetary gear set to the first ring assembly when thetransmission is in continuously variable mode.

In some embodiments, when the first brake is engaged and the secondbrake is disengaged, the first ring assembly of the variator and theplanetary gear carrier are held fixed, to engage an infinitely variablemode. In some embodiments, in the infinitely variable mode, the variatorprovides a reverse function, a standstill function, and a low speedfunction.

In some embodiments, a transition between continuously variable mode andinfinitely variable mode is accomplished by simultaneously releasing oneof the first brake and the second brake while applying the other of thefirst brake and the second brake.

In some embodiments, the variator continuously changes its torque ratiosin both the continuously variable mode and infinitely variable mode tooptimize performance or fuel consumption. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to achieve an ideal ratio forvariable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode have overlapping rotation speeds of the second ringassembly (or transmission output). In some embodiments, rotation speedrange of the infinitely variable mode is wider than the rotation speedin the continuously variable mode. In some embodiments, the relationshipof rotation speeds of the second ring assembly in the continuouslyvariable mode and the second ring assembly in the infinitely variablemode, and the rotation speed of the input shaft from the engine is asshown in FIG. 7.

Provided herein is a variable transmission comprising: an input shaft; avariator comprising a first ring assembly, a second ring assembly, and acarrier assembly; a planetary gear set comprising a sun gear drivinglyengaged with the input shaft, a ring gear drivingly engaged with thevariator carrier assembly, and one or more planet gears on a planetcarrier, the planet gears disposed in mechanical engagement between thesun gear and the ring gear; a first brake coupled to the ring gear andconfigured to hold the ring gear fixed when the first brake is engaged;and a second brake coupled to the planet carrier and the first ringassembly, and configured to hold the planet carrier fixed when thesecond brake is engaged; and wherein the second ring assembly isdrivingly engaged with the output of the variable transmission.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the first brake is engaged and the secondbrake is disengaged, the ring gear and the variator carrier assembly arefixed to engage a continuously variable mode. In some embodiments, inputpower passes through the planetary carrier to the first ring assemblywhen the transmission is in the continuously variable mode.

In some embodiments, when the second brake is engaged and the firstbrake is disengaged, the planet carrier and the first ring assembly areheld fixed by the second brake to engage an infinitely variable mode. Insome embodiments, power passes through the ring gear of the planetarygear set, to the variator carrier assembly when the transmission is inthe infinitely variable mode. In some embodiments, in the infinitelyvariable mode the variator provided a reverse function, a standstillfunction and a low speed function.

In some embodiments, a transition between continuously variable mode andinfinitely variable mode is accomplished by simultaneously releasing oneof the first brake and the second brake while applying the other of thefirst brake and the second brake.

In some embodiments, the variator continuously changes its torque ratiosin both the continuously variable mode and infinitely variable mode tooptimize performance or fuel consumption. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to achieve an ideal ratio forvariable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode provide overlapping rotation speeds of the second ringassembly. In some embodiments, the continuously variable mode andinfinitely variable mode have lower rotation speeds of the second ringassembly than a rotation speed of the input shaft. In some embodiments,the relationship of rotation speeds of the second ring assembly in thecontinuously variable mode and the second ring assembly in theinfinitely variable mode, and the rotation speed of the input shaft fromthe engine is as shown in FIG. 9.

Provided herein is a variable transmission comprising: an input shaft, avariator comprising a first ring assembly, a second ring assembly, and acarrier assembly, wherein the second ring assembly is drivingly engagedto an output of the variable transmission; a planetary gear setcomprising a sun gear drivingly engaged with the input shaft, a ringgear drivingly engaged with the second ring assembly, and one or moreplanet gears on a planet carrier, the planet gears disposed inmechanical engagement between the sun gear and the ring gear; a firstbrake coupled to the first ring assembly and configured to hold the ringgear of the planetary gear set and the first ring assembly fixed whenthe first brake is engaged; and a second brake coupled to the planetcarrier and the variator carrier assembly, and configured to hold theplanet carrier and the variator carrier assembly fixed when the secondbrake is engaged.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the second brake is engaged and the firstbrake is disengaged, the planet carrier and the variator carrierassembly are held fixed to engage a continuously variable mode. In someembodiments, power passes through the planetary gear set ring gear andgoes to the first ring assembly when the transmission is in thecontinuously variable mode.

In some embodiments, when the first brake is engaged and the secondbrake is disengaged, the ring gear and the first ring assembly are heldfixed to engage an infinitely variable mode. In some embodiments, powerpasses through the planet carrier to the variator carrier assembly whenthe transmission is in the infinitely variable mode.

In some embodiments, in the infinitely variable mode the variatorprovides a reverse function, a standstill function and a low speedfunction. In some embodiments, a transition between continuouslyvariable mode and infinitely variable mode is accomplished bysimultaneously releasing one of the first brake and the second brakewhile applying the other of the first brake and the second brake.

In some embodiments, the variator continuously changes its torque ratiosin both the continuously variable mode and infinitely variable mode tooptimize performance or fuel consumption. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to achieve an ideal ratio forvariable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode provide a gap in rotation speeds of the second ringassembly. In one embodiment, the gap is compensated by engine speedadjustment. In some embodiments, the relationship of rotation speeds ofthe second ring assembly in the continuously variable mode and thesecond ring assembly in the infinitely variable mode, and the rotationspeed of the CVT input from the engine is as shown in FIG. 11.

Provided herein is a variable transmission comprising: an input shaft; aclutch comprising a first clutch member coupled to the input shaft and asecond clutch member; a variator comprising, a carrier assembly, a firstring assembly having the second clutch member formed thereon, and asecond ring assembly, and wherein the second ring assembly is drivinglyengaged to an output of the variable transmission; a planetary gear setcomprising a sun gear drivingly engaged with the input shaft, one ormore planet gears on a planet carrier, wherein the planet carrier isdrivingly engaged with the variator carrier, and wherein a ring gear ofthe planetary gear set is held fixed; and a first brake coupled to thefirst ring assembly configured to hold the first ring assembly fixedwhen the first brake is engaged, wherein the first ring assembly isdrivingly engaged with the input shaft when the first clutch memberengages the second clutch member.

In some embodiments, the variable transmission comprises a combinedcontinuously variable/infinitely variable mode (CVP/IVP mode), or aninfinitely variable mode.

In some embodiments, when the clutch is engaged, both the first ringassembly and the variator carrier are driven in order to engage thecombined continuously variable/infinitely variable mode (CVP/IVP mode).In some embodiments, the variable transmission in the combinedcontinuously variable/infinitely variable mode generates rotation speedsof the second ring assembly between speeds generated in a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the first ring assembly is held fixed with thefirst brake and the clutch is disengaged, the infinitely variable modeis engaged. In some embodiments, the power passes through the planetcarrier of the planetary gear set and to the variator carrier in theinfinitely variable mode. In some embodiments, the variator provides areverse function, a standstill function and a low speed function in theinfinitely variable mode.

In some embodiments, a transition between the continuouslyvariable/infinitely variable mode (CVP/IVP mode) and the infinitelyvariable (IVP) mode is accomplished by engaging/disengaging the clutchand engaging/disengaging the first brake. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to optimize performance orfuel consumption. In some embodiments, the variator continuously changesits torque ratios in both the continuously variable mode and infinitelyvariable mode to achieve an ideal ratio for variable transmission.

In some embodiments, the CVP/IVP mode and infinitely variable modeprovide a gap in rotation speeds of the second ring assembly. In oneembodiment, the gap is compensated by engine speed adjustment. In someembodiments, the relationship of rotation speeds of the second ringassembly in the CVP/IVP mode and the second ring assembly in theinfinitely variable mode, and the rotation speed of the input shaft fromthe engine is as shown in FIG. 13.

Provided herein is a vehicle driveline comprising an engine, a variabletransmission of any of configuration described herein or obvious to oneof skill in the art upon reading the disclosure herein, and a vehicleoutput. In some embodiments, the vehicle output comprises a wheeldifferential and one or more wheels of a vehicle. In some embodiments,the vehicle output comprises a wheel differential and a drive axle. Insome embodiments, the dampener is disposed between the engine and thevariable transmission. In some embodiments, the dampener comprises atleast one torsional spring.

Provided herein is a method comprising providing a variable transmissionof any of configuration described herein or obvious to one of skill inthe art upon reading the disclosure herein.

Provided herein is a method comprising providing a vehicle driveline ofany of configuration described herein or obvious to one of skill in theart upon reading the disclosure herein.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 is a side sectional view of a continuously variable planetary(CVP) transmission;

FIG. 2 is a magnified, side sectional view of a ball and ring of the CVPtransmission of FIG. 1;

FIG. 3 is a block diagram of a continuously variable transmission (CVT)used in an automobile;

FIG. 4 is a block diagram of a continuously variable transmission (CVT)according to an embodiment of the present disclosure used in anautomobile having both a continuously variable mode and an infinitelyvariable mode;

FIG. 5 is a graph of a speed diagram of the second (output) ringassembly in FIG. 4;

FIG. 6 is a block diagram of a continuously variable transmission (CVT)according to another embodiment of the present disclosure used in anautomobile having both a continuously variable CVP mode and aninfinitely variable planetary mode;

FIG. 7 is a graph of a speed diagram of the second (output) ringassembly in FIG. 6;

FIG. 8 is a block diagram of a continuously variable transmission CVTaccording to another embodiment of the present disclosure used in anautomobile having both a continuously variable mode and an infinitelyvariable mode;

FIG. 9 is a graph of a speed diagram of the second (output) ringassembly in FIG. 8;

FIG. 10 is a block diagram of a continuously variable transmission (CVT)according to another embodiment of the present disclosure used in anautomobile having both a continuously variable mode and an infinitelyvariable mode;

FIG. 11 is a graph of a speed diagram of the second (output) ringassembly in FIG. 10;

FIG. 12 is a block diagram of a continuously variable transmission (CVT)according to another embodiment of the present disclosure used in anautomobile having both a continuously variable mode and an infinitelyvariable mode; and

FIG. 13 is a graph of a speed diagram of the second (output) ringassembly in FIG. 12.

DETAILED DESCRIPTION OF THE INVENTION

Besides the automatic and manual transmissions now commonly used onautomobile vehicles, Continuously Variable Transmissions or CVTs havebeen developed. Those CVTs are of many types: belts with variablepulleys, toroidal, and conical, for non-limiting example. The principleof a CVT is that it enables the engine to run at its most efficientrotation speed by steplessly changing the transmission ratio as afunction of the speed of the car and the torque demand (throttleposition) of the driver. If needed for example when accelerating, theCVT can also shift to the most optimum ratio providing more power. A CVTcan change the ratio from the minimum to the maximum ratio without anyinterruption of the power transmission, as opposed to the usualtransmissions which require an interruption of the power transmission bydisengaging to shift from one discrete ratio to engage the next ratio.

A specific use of CVTs is the Infinite Variable Transmission or IVT.Where the CVT is limited to positive speed ratios, the IVT configurationcan perform a neutral gear and even reverse ratios steplessly. A CVT canbe used as an IVT in some driveline configurations.

Provided herein are configurations based on a ball type CVT, also knownas CVP, for continuously variable planetary. Aspects of the CVTs aredescribed in US2006084549 or AU2011224083A1, incorporated herein byreference in their entirety. The type of CVT used herein is composed ofa plurality of variator balls, depending on the application, two discsor annular rings each having an engagement portion that engages thevariator balls. The engagement portions may be in a conical or toroidalconvex or concave surface contact with the variator balls, as input andoutput. The CVT may include an idler contacting the balls as well asshown on FIG. 1. The variator balls are mounted on axes, themselves heldin a cage or carrier allowing changing the ratio by tilting the variatorballs' axes. Other types of ball CVTs also exist, like the one producedby Milner but are slightly different. These alternative ball CVTs areadditionally contemplated herein. The working principle generallyspeaking, of a ball-type CVT is shown in FIG. 2.

The CVP itself works with a traction fluid. The lubricant between theball and the conical rings acts as a solid at high pressure,transferring the power from the first ring assembly, through thevariator balls, to the second ring assembly. By tilting the variatorballs' axes, the ratio can be changed between input and output. When theaxis of each of the variator balls is horizontal the ratio is one, whenthe axis is tilted the distance between the axis and the contact pointchange, modifying the overall ratio. All the variator balls'axles aretilted at the same time with a mechanism included in the cage.

In a car, the CVT is used to replace traditional transmission and islocated between the engine (ICE or internal combustion engine) and thedifferential as shown on FIG. 3. A torsional dampener (alternativelycalled a damper) may be introduced between the engine and the CVT toavoid transferring torque peaks and vibrations that could damage theCVT. In some configurations this dampener can be coupled with a clutchfor the starting function.

Embodiment transmissions (and a resulting drivelines) are shown in FIGS.4, 6, 8, 10, and 12. The central part of these configurations is avariator, such as variator 10 a (also depicted as elements 10 b-e). Suchvariators may typically comprise the tilting ball type CVPs describedabove. Such variators 10 a-10 e typically each comprises a first ringassembly, a second ring assembly, and a carrier assembly disposedtherebetween. Referring now to FIG. 4, variator 10 a is shown comprisinga first ring assembly 12 a, a second ring assembly 11 a, and a carrierassembly 13 a (also referred to as a “variator carrier assembly” or“variator carrier”). The carrier assembly typically includes a pluralityof variator balls having tiltable axle shafts as described herein. Insome embodiments, the first ring assembly is rotatably disposed in ahousing; the first ring assembly comprises a first variator ballengagement surface that is in driving engagement with a plurality ofvariator balls of the carrier assembly. In some embodiments the firstring assembly may be drivingly engaged with input shaft.

A first variator ball engagement surface is formed in a distal end ofthe first ring assembly. As meant herein, when describing the ringassemblies of a variator, distal means the portion of the ring assemblyclosest to the variator balls. In some embodiments, the first variatorball engagement surface is a conical surface or a concave or convextoroidal surface in contact with or slightly spaced apart from each ofthe variator balls. In some embodiments, the first variator ballengagement surface is in driving engagement with each of the variatorballs of the carrier assembly through one of a boundary layer typefriction and an elastohydrodynamic film.

The variator carrier assemblies (13 a-e) of some embodiments shown inFIGS. 4, 6, 8, 10, and 12, may be rotatably disposed in the housing andis drivingly engaged with the first ring assembly. In some embodiments,the carrier assembly may comprises an annular arrangement of theplurality of tiltable variator balls each having tiltable ball axleshafts. A cage of the carrier assembly may be configured to be preventedfrom rotating relative to the housing by a grounding device linked tosaid ground. In some embodiments, each of the ball axle shafts isadjusted using a cam style tilting mechanism. In some embodiments, eachof the ball axle shafts is adjusted using a split carrier axle skewingmechanism.

As depicted in FIGS. 4, 6, 8, 10, and 12, at least, the second ringassembly is rotatably disposed in the housing. The second ring assemblycomprises a second variator ball engagement surface that is in drivingengagement with variator balls of the carrier assembly. In someembodiments, the second variator ball engagement surface is formed in adistal end of the second ring assembly. In some embodiments, the secondvariator ball engagement surface is a conical surface or a concave orconvex toroidal surface in contact with or slightly spaced apart fromeach of the variator balls. In some embodiments, the second variatorball engagement surface is in driving engagement with each of thevariator balls of the carrier assembly through one of a boundary layertype friction and an elastohydrodynamic film.

A ball ramp on each side of the variator (depicted as elements 15 a-e)provides the clamping force necessary to transfer the torque. Ballramps, indicated in FIGS. 4, 6, 8, 10, and 12 by a circle between a pairof vertical lines, making up a first thrust ring on the first ringassembly and a second thrust ring on the second ring assembly aredisposed between components of the variable transmission as shown togenerate an amount of axial force necessary for proper operation of thevariable transmission (i.e. transfer of torque); however, it isunderstood that the amount of axial force necessary for proper operationmay be generated by a clamping mechanism (not shown) or as a loadapplied during assembling of the variable transmission. Thus, asdepicted in FIGS. 4, 6, 8, 10, and 12, a ball ramp on each side of thevariator provides the clamping force necessary to transfer the torque inthis embodiment.

Provided herein is a variable transmission comprising; a power inputshaft; a planetary gear set mechanically coupled to the power inputshaft, a variator comprising, a variator carrier assembly, a first ringassembly, and a second ring assembly; and various combinations of brakesand clutches.

In some embodiments, the variable transmission comprises a variatorhaving a continuously variable mode, an infinitely variable mode or acombination thereof.

In some embodiments the variable transmission can provide a reversefunction, a standstill function and a low speed function.

In some embodiments, the transition between continuously variabletransmission mode and infinitely variable transmission mode isaccomplished by simultaneously releasing one of the brakes and applyingthe other brake.

In some embodiments, the transition between continuously variabletransmission mode and infinitely variable transmission mode isaccomplished by releasing the clutch and engaging the brake.

In some embodiments, the variator is able to continuously change itstorque ratios in both the continuously variable mode and infinitelyvariable mode to provide the best ratio achievable for the engine tooptimize performance or fuel consumption.

Provided herein is a variable transmission (VT) comprising: an inputshaft; a planetary gear set drivingly engaged with the input shaftthough its planet carrier; a first brake mechanically coupled to a ringgear of the planetary gear set; a variator comprising a variator carrierassembly, a first ring assembly, and a second ring assembly, the carrierof the variator mechanically coupled to a ring gear of the planetarygear set; and a second brake mechanically coupled to a sun gear of theplanetary gear set and to the first ring assembly, a second ringassembly is drivingly engaged with the output of the VT. Such a variabletransmission is depicted in the embodiment of FIG. 4.

FIG. 4 depicts a VT of a particular embodiment of the present inventioncomprising: an input shaft 1; a planetary gear set 5 a drivingly engagedwith the input shaft though its planet carrier 8 a; a first brake 16mechanically coupled to a ring gear 9 a of the planetary gear set; avariator 10 a (as described elsewhere in this application) comprising avariator carrier assembly 13 a, a set of tilting balls 14 a, a firstring assembly 12 a, and a second ring assembly 11 a, the variatorcarrier assembly is mechanically coupled to the ring gear 9 a of theplanetary gear set 5 a; and a second brake 17 may be mechanicallycoupled to the sun gear 6 a of the planetary gear set and to the firstring assembly 12 a. The second ring assembly 11 a is drivingly engagedwith the output of the VT.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode. In some embodiments whenthe first brake is engaged and the second brake disengaged, the ringgear of the planetary gear set and a variator carrier assembly (alsoreferred to as a “variator carrier” or “carrier of the variator”) areheld fixed, thereby engaging the continuously variable mode. In someembodiments power may pass through the sun gear of the planetary gearset to the first ring assembly when the transmission is in continuouslyvariable mode. For example, in the embodiment of FIG. 4: when the firstbrake is engaged and the second brake is disengaged, the ring gear 9 aof the planetary gear set 50 a and variator carrier assembly 13 a areheld fixed, thereby engaging a continuously variable mode.

In some embodiments when the second brake is engaged and the first brakeis disengaged the sun gear of the planetary gear set and the first ringassembly are held fixed, thereby engaging an infinitely variable mode.In some embodiments, power passes through the ring gear of the planetarygear set to a carrier of the variator in the infinitely variable mode.In some embodiments, in the infinitely variable mode, the variatorprovides a reverse function, a standstill function, and a low speedfunction. For example in the embodiment of FIG. 4, when the second brakeis engaged and the first brake is disengaged, the sun gear 6 a of theplanetary gear set 5 a and the first ring assembly are held fixed,thereby engaging an infinitely variable mode. In such a mode, power maypass through the ring gear 9 a of the planetary gear set 5 a to thevariator carrier assembly 13 a.

In some embodiments, a transition between continuously variable mode andinfinitely variable mode is accomplished by simultaneously releasing oneof the first brake and the second brake while applying the other of thefirst brake and the second brake. In some embodiments, the variatorcontinuously changes its torque ratios in both the continuously variablemode and infinitely variable mode to optimize performance or fuelconsumption. In some embodiments, the variator continuously changes itstorque ratios in both the continuously variable mode and infinitelyvariable mode to achieve an ideal ratio for variable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode provide a gap in rotation speeds of the second ringassembly. In one embodiment, the gap is compensated by engine speedadjustment. In some embodiments, the relationship of rotation speeds ofthe second ring assembly in the continuously variable mode and thesecond ring assembly in the infinitely variable mode, and the rotationspeed of the input shaft from the engine is as shown in FIG. 5.

Provided herein is a variable transmission comprising: an input shaft; aring gear of the planetary gear set drivingly engaged with the inputshaft; a variator comprising a variator carrier assembly, a first ringassembly, and a second ring assembly; a planetary gear carrier coupledto a first brake and to the first ring assembly; and a sun gear coupledto a second brake and a variator carrier; a second ring assembly of thevariator drivingly engaged to the output of the VT.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode. In some embodiments, whenthe second brake is engaged and the first brake is disengaged the sungear of the planetary gear set is fixed together with the variatorcarrier assembly to engage a continuously variable mode. An example ofsuch an embodiment is depicted in FIG. 6 and is discussed below.

In some embodiments when the first brake is engaged and the second brakedisengaged an input ring assembly (typically the first ring assembly) ofthe variator and the planetary gear carrier (also referred to as “planetcarrier” or “planetary carrier assembly”) is fixed, thereby engaging aninfinitely variable mode. In some embodiments, in the infinitelyvariable mode, the variator provides a reverse function, a standstillfunction, and a low speed function (forward speed). An example of suchan embodiment is depicted in FIG. 6.

In some embodiments, an example of which is depicted in FIG. 6, atransition between continuously variable mode and infinitely variablemode is accomplished by simultaneously releasing one of the first brakeand the second brake while applying the other of the first brake and thesecond brake.

In such embodiments, the variator continuously changes its torque ratiosin both the continuously variable mode and infinitely variable mode tooptimize performance or fuel consumption. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to achieve an ideal ratio forvariable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode have overlapping rotation output speeds. For example, inthe embodiment depicted in FIG. 6, the continuously variable mode andthe infinitely variable mode may have overlapping rotation speeds of thesecond ring assembly. In some embodiments, a rotation speed range of theinfinitely variable mode may be wider than the rotation speed in thecontinuously variable mode. FIG. 7 shows an exemplary relationshipbetween rotation speeds of the second ring assembly in the continuouslyvariable mode and the second ring assembly in the infinitely variablemode.

Provided herein is a variable transmission comprising: an input shaft; avariator comprising a first ring assembly, a second ring assembly, and acarrier assembly (also referred to as the “variator carrier assembly”),wherein the second ring assembly is drivingly engaged with the output ofthe VT ; a planetary gear set comprising a sun gear drivingly engagedwith the input shaft, a ring gear drivingly engaged with the variatorcarrier assembly, and one or more planet gears on a planet carrier (alsoreferred to as a “planetary carrier assembly”), the planet gearsdisposed in mechanical engagement between the sun gear and the ringgear; a first brake coupled to the ring gear and configured to hold thering gear fixed when the first brake is engaged; and a second brakecoupled to the planet carrier and the first ring assembly, andconfigured to hold the planet carrier and the first ring assembly fixedwhen the second brake is engaged. An example of such an embodiment isdepicted in FIG. 8.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the first brake is engaged and the secondbrake is disengaged, the ring gear and the variator carrier assembly areboth fixed to engage a continuously variable mode. In some embodiments,input power passes through the planetary carrier to the first ringassembly when the transmission is in the continuously variable mode.

In some embodiments, when the second brake is engaged and the firstbrake is disengaged, the planet carrier and the first ring assembly areheld fixed by the second brake to engage an infinitely variable mode. Insome embodiments, power passes through the ring of the planetary gearset, to the variator carrier when the transmission is in the infinitelyvariable mode. In some embodiments, in the infinitely variable mode thevariator provided a reverse function, a standstill function and a lowspeed function.

In some embodiments, a transition between continuously variable mode andinfinitely variable mode is accomplished by simultaneously releasing oneof the first brake and the second brake while applying the other of thefirst brake and the second brake.

In some embodiments, the variator continuously changes its torque ratiosin both the continuously variable mode and infinitely variable mode tooptimize performance or fuel consumption. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to achieve an ideal ratio forvariable transmission.

In some embodiments, the continuously variable mode and infinitelyvariable mode provide overlapping rotation speeds of the second ringassembly. In some embodiments, the continuously variable mode andinfinitely variable mode have lower rotation speeds of the second ringassembly than a rotation speed of the input shaft. In some embodiments,the relationship of rotation speeds of the second ring assembly in thecontinuously variable mode and the second ring assembly in theinfinitely variable mode, and the rotation speed of the input shaft fromthe engine is as shown in FIG. 9.

Provided herein is a variable transmission comprising: a variatorcomprising a first ring assembly, a second ring assembly drivinglyengaged to the output of the VT, and a carrier assembly; a planetarygear set comprising a sun gear drivingly engaged with the input shaft, aring gear drivingly engaged with the first ring assembly, and one ormore planet gears on a planet carrier, the planet gears disposed inmechanical engagement between the sun gear and the ring gear; a firstbrake coupled to the first ring assembly and configured to hold the ringgear of the planetary gear set and the first ring assembly fixed whenthe first brake is engaged; and a second brake coupled to the planetcarrier and a variator carrier of the carrier assembly, and configuredto hold the planet carrier and the variator carrier fixed when thesecond brake is engaged.

In some embodiments, the variable transmission comprises a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the second brake is engaged and the firstbrake is disengaged, the planetary carrier assembly and the variatorcarrier are held fixed to engage a continuously variable mode. In someembodiments, power passes through the planetary ring gear and goes tothe first ring assembly when the transmission is in the continuouslyvariable mode.

In some embodiments, when the first brake is engaged and the secondbrake is disengaged, the ring gear and the first ring assembly are heldfixed to engage an infinitely variable mode. In some embodiments, powerpasses through the planetary carrier assembly to the variator carrierassembly when the transmission is in the infinitely variable mode.

In some embodiments, in the infinitely variable mode the variatorprovided a reverse function, a standstill function and a low speedfunction. In some embodiments, a transition between continuouslyvariable mode and infinitely variable mode is accomplished bysimultaneously releasing one of the first brake and the second brakewhile applying the other of the first brake and the second brake.

In some embodiments, the variator continuously changes its torque ratiosin both the continuously variable mode and infinitely variable mode tooptimize performance or fuel consumption. In some embodiments, thevariator continuously changes its torque ratios in both the continuouslyvariable mode and infinitely variable mode to achieve an ideal ratio forthe VT.

In some embodiments, the continuously variable mode and infinitelyvariable mode provide a gap in rotation speeds of the second ringassembly. In one embodiment, the gap is compensated by engine speedadjustment. In some embodiments, the relationship of rotation speeds ofthe second ring assembly in the continuously variable mode and thesecond ring assembly in the infinitely variable mode, and the rotationspeed of the input shaft from the engine is as shown in FIG. 11.

Provided herein is a variable transmission comprising: an input shaft; aclutch comprising a first clutch member coupled to the input shaft and asecond clutch member; a variator comprising a first ring assembly havingthe second clutch member formed thereon, a second ring assemblydrivingly engaged to the output of the VT, and a carrier assembly; aplanetary gear set comprising a sun gear drivingly engaged with theinput shaft, one or more planet gears on a planet carrier (also referredto as a “planetary carrier assembly”) that is drivingly engaged with thevariator carrier assembly, a ring gear, wherein the ring gear of theplanetary gear set is held fixed; and a first brake coupled to the firstring assembly configured to hold the first ring assembly fixed when thefirst brake is engaged, wherein the first ring assembly is drivinglyengaged with the input shaft when the first clutch member engages thesecond clutch member.

In some embodiments, the variable transmission comprises a combinedcontinuously variable/infinitely variable mode (CVP/IVP mode), or aninfinitely variable mode.

In some embodiments, when the clutch is engaged, both the first ringassembly and the variator carrier are driven in order to engage thecombined continuously variable/infinitely variable mode (CVP/IVP mode).In some embodiments, the variable transmission in the combinedcontinuously variable/infinitely variable mode generates rotation speedsof the second ring assembly between speeds generated in a continuouslyvariable mode and an infinitely variable mode.

In some embodiments, when the first ring assembly is held fixed with thefirst brake and the clutch is disengaged, the infinitely variable modeis engaged. In some embodiments, the power passes through the planetcarrier of the planetary gear set and to the variator carrier in theinfinitely variable mode. In some embodiments, the variator provides areverse function, a standstill function and a low speed function in theinfinitely variable mode.

In some embodiments, a transition between the continuouslyvariable/infinitely variable mode (CVP/IVP mode) and the infinitelyvariable (IVP) mode is accomplished by engaging/disengaging the clutchand engaging/disengaging the brake. In some embodiments, the variatorcontinuously changes its torque ratios in both the continuously variablemode and infinitely variable mode to optimize performance or fuelconsumption. In some embodiments, the variator continuously changes itstorque ratios in both the continuously variable mode and infinitelyvariable mode to achieve an ideal ratio for the VT.

In some embodiments, the CVP/IVP mode and infinitely variable modeprovide a gap in rotation speeds of the second ring assembly. In oneembodiment, the gap is compensated by engine speed adjustment. In someembodiments, the relationship of rotation speeds of the second ringassembly in the CVP/IVP mode and the second ring assembly in theinfinitely variable mode, and the rotation speed of the input shaft fromthe engine is as shown in FIG. 13.

Provided herein is a vehicle driveline comprising an engine, a variabletransmission of any of configuration described herein or obvious to oneof skill in the art upon reading the disclosure herein, and a vehicleoutput. In some embodiments, the vehicle output comprises a wheeldifferential and one or more wheels of a vehicle. In some embodiments,the vehicle output comprises a wheel differential and a drive axle. Insome embodiments, the dampener is disposed between the engine and thevariable transmission. In some embodiments, the dampener comprises atleast one torsional spring.

Provided herein is method comprising providing a variable transmissionof any of configuration described herein or obvious to one of skill inthe art upon reading the disclosure herein.

Provided herein is a method comprising providing a vehicle driveline ofany of configuration described herein or obvious to one of skill in theart upon reading the disclosure herein.

Example 1

An exemplary embodiment of the invention is shown in FIG. 4 comprisingCVT 3 a. FIG. 4 shows CVT 3 a which may be disposed within a drivelineof a vehicle. The driveline may comprise a motor such as an internalcombustion engine (ICE) 100, which may be connected to CVT 3 a via aninput shaft 1 a, and may optionally feature a clutch and or damper 2drivingly engaged therebetween. The output 50 a of CVT 3 a may bedrivingly engaged to a vehicle differential and wheels 4. The CVT 3 a ofthe FIG. 4 embodiment is depicted comprising: an input shaft 1 a; aplanetary gear set 5 a drivingly engaged with the input shaft though itsplanet carrier (also referred to as “planetary carrier assembly”) 8 a; afirst brake 16 mechanically coupled to a ring gear 9 a of the planetarygear set; a variator 10 a (as described elsewhere in this application)comprising a variator carrier assembly 13 a, a set of tilting balls 14a, a first ring assembly 12 a, and a second ring assembly 11 a, thevariator carrier assembly is mechanically coupled to the ring gear 9 aof the planetary gear set 5 a; and a second brake 17 may be mechanicallycoupled to the sun gear 6 a of the planetary gear set and to the firstring assembly 12 a. The second ring assembly 11 a is drivingly engagedwith the output 50 a of the CVT. The configuration of FIG. 4 includes acontinuously variable mode as well as an infinitely variable modeproviding a standstill, reverse, and starting function.

The CVT 3 a of FIG. 4, comprises a continuously variable mode and aninfinitely variable mode. When the first brake 16 is engaged and thesecond brake 17 is disengaged, the ring gear 9 a of the planetary gearset and the variator carrier assembly 13 a (also referred to as a“variator carrier” or “carrier of the variator”) are held fixed, therebyengaging the continuously variable mode. In such a mode power may passthrough the sun gear of the planetary to the first ring assembly therebyallowing a continuously variable mode. The infinitely variable mode isengaged when the second brake 17 is engaged and the first brake 16 isdisengaged. When the second brake is engaged and the first brake isdisengaged, the first ring assembly 12 a and the sun gear 6 a are heldfixed and the variator carrier assembly is driven by the input shaft 1 athrough the planet carrier 8 a and ring gear 9 a. Tilting the balls 14 aof variator 10 a will allow the second ring assembly 11 a and CVT output50 a to steplessly transition from reverse to neutral to forward speeds,thereby achieving an infinitely variable mode of CVT 3 a.

FIG. 5 shows the speed diagram of the planetary concept of FIG. 4.

The axis of FIG. 5 represents the rotation speed of the variator secondring assembly.

As described above, the continuously variable mode is used by applyingthe first brake 16, holding fixed the ring 9 a of the planetary gear set5 a as well as the carrier of the variator balls (variator carrierassembly 13 a). The power passes through the sun 6 a and goes to thevariator first ring assembly 12 a. The rotation speed achievable incontinuously variable mode can be observed as segment 19 on the speeddiagram. The overall ratio is the product of the planetary ratio, thevariator ratio and the final drive ratio.

In an infinitely variable mode, the second brake 17 is applied, holdingthe sun gear 6 a of the planetary 5 a and the first ring assembly 12 afixed. The power passes through the ring gear 9 a of the planetary gearset 5 a and goes to the carrier of the variator balls 13 a. This modeprovides a reverse function as well as a standstill and a low speed. Theachievable rotation speeds in the infinitely variable mode can beobserved as segment 20 on the speed diagram. The overall ratio is theproduct of the planetary ratio, the variator ratio and the final driveratio. As a reference an example ICE rotation speed is shown at point22.

A small gap may exist between the speeds ranges 19 and 20 of thecontinuously variable mode and infinitely variable mode and will forcethe engine to change its speed in order to allow all the vehicle speed.But as this gap is very small, the user will not feel it, the enginespeed will only slightly vary, and this design does not need anadditional gearbox to help avoid it, although one may be providednonetheless in an alternative embodiment.

The transition between the continuously variable mode and infinitelyvariable mode is done by simultaneously releasing one of the first brake16 and the second brake 17, and applying the other one. This embodimentis able to change continuously its ratio in the continuously variablemode and infinitely variable mode to provide the best ratio achievablefor the engine in function of the objectives of performance or fuelconsumption. In a manual or automatic transmission, only somepredetermined and discrete ratios are available and an interruption ofthe power transmission is needed to shift the ratio. Thereby, in theembodiment of FIG. 4, the only interruptions of power in this device arethe shifting of modes. An additional advantage of this configuration isthat a small variator can be chosen.

Example 2

Provided herein is an embodiment as shown in FIG. 6 comprising aplanetary gear set and two brakes to hold either the carrier or the sunfixed. Such an exemplary embodiment of the invention is shown in FIG. 6comprising CVT 3 b. FIG. 6 shows CVT 3 b which may be disposed within adriveline of a vehicle. The driveline may comprise a motor such as anICE 100, which may be connected to CVT 3 b via an input shaft 1 b, andmay optionally feature a clutch and or damper 2 drivingly engagedtherebetween. The output 50 b of CVT 3 b may be drivingly engaged to avehicle differential and wheels 4. The CVT 3 b of the FIG. 6 embodimentis depicted as comprising: an input shaft 1 b; a variator 10 bcomprising a first ring assembly 11 b, a second ring assembly 12 b, avariator carrier assembly 13 b, and a set of tilting balls 14 b; aplanetary gear set 5 b comprising a ring gear 9 b, sun gear 6 b, planets7 b and a planetary carrier assembly 8 b; a first brake 16; a secondbrake 17; and a CVT output 50 b. The configuration of FIG. 6 includes acontinuously variable mode as well as an infinitely variable modeproviding a standstill, reverse, and starting function.

In the embodiment of FIG. 6, the motor 100 is connected to the ring gear9 b of the planetary gear set 5 b via input shaft 1 b. The sun gear 6 bof the gear set is connected to a second brake 17 and to the variatorcarrier assembly 13 b. The planetary carrier 8 b of the planetary gearset is linked to the first ring assembly 11 b of the variator 10 b andcan be held fixed by a first brake 16. The second ring assembly 12 b ofthe variator 10 b is drivingly engaged to the differential (and wheels)4 of the vehicle through CVT output 50 b. This may be achieved using aseries of gears as shown in FIG. 6 or in another manner.

FIG. 7 shows the speed diagram of the configuration shown in FIG. 6.

The axis of FIG. 7 represents the rotation speed of the variator secondring assembly.

In the embodiment of FIG. 6, the continuously variable mode is used byapplying the second brake 17, holding fixed the sun 6 b of the planetarygear set as well as the carrier of the variator 13 b. The power passesthrough the ring 9 b and goes to the first ring assembly 11 b. Therotation speed achievable in continuously variable mode can be observedas segment 25 on the speed diagram. The overall ratio is the product ofthe planetary ratio, the variator ratio and the final drive ratio.

In infinitely variable mode of embodiment of FIG. 6, the first brake 16is applied, holding the carrier of the planetary and the first ringassembly fixed. The power passes through the sun 6 b of the planetarygear set 5 b and goes to the variator carrier 13 b. The power drivesvariator carrier 13 b while the first ring assembly 11 b remainsstationary. As in the embodiment of FIG. 5, tilting the balls 14 ballows the second ring assembly to steplessly transition from reverse,neutral, and forward speeds. Thus an infinitely variable mode isachieved. This mode provides a reverse function as well as a standstilland a low speed. It can be observed as segment 26 on the speed diagramof FIG. 7. An example motor speed 22 is shown as a reference. Theoverall ratio in the infinitely variable mode is the product of theplanetary ratio, the variator ratio and the final drive ratio.

The transition between the two modes as embodied in FIG. 6 is done bysimultaneously releasing one of the first and second brakes and applyingthe other of the first and second brakes. This device is able to changecontinuously its ratio to provide the best ratio achievable for theengine in function of the objectives of performance or fuel consumption.In a manual or automatic transmission, only some predetermined anddiscrete ratios are available and an interruption of the powertransmission is needed to shift of ratio. The only interruptions ofpower in this device are the modes shifting.

Example 3

Provide herein is a configuration of a variable transmission anddriveline that uses a planetary gear set and two brakes to hold eitherthe ring or the carrier fixed as shown in FIG. 8. Such an exemplaryembodiment of the invention is shown in FIG. 8 comprising CVT 3 c. FIG.8 shows CVT 3 c which may be disposed within a driveline of a vehicle.The driveline may comprise a motor such as an ICE 100, which may beconnected to CVT 3 c via an input shaft 1 c, and may optionally featurea clutch and or damper 2 drivingly engaged therebetween. The output 50 cof CVT 3 c may be drivingly engaged to a vehicle differential and wheels4. The CVT 3 c of the FIG. 8 embodiment is depicted as comprising: aninput shaft 1 c; a variator 10 c, comprising a first ring assembly 12 c,a second ring assembly 11 c, a variator carrier assembly 13 c, and a setof tilting balls 14 c; a planetary gear set 5 c comprising a ring gear 9c, sun gear 6 c, planets 7 c and a planetary carrier assembly 8 c; afirst brake 28; a second brake 27; and the CVT output 50 c. Theconfiguration of FIG. 6 includes a continuously variable mode as well asan infinitely variable mode providing a standstill, reverse, andstarting function. The central part of that configuration is thevariator 10 c, the operation of which is described previously in thedocument. A ball ramp 15 c on each side of the variator 10 c providesthe clamping force necessary to transfer the torque. Having two brakes,this configuration includes a continuously variable mode as well as aninfinitely variable mode providing a standstill, reverse and startingfunction. No starting device like a slipping clutch or torque converteris required, since the infinitely variable mode takes care of thestarting function.

The motor 100 is connected to the sun 6 c of the planetary gear set 5 c.The planetary carrier 8 c connected to the second brake 27 and then tothe first ring assembly 12 c. The ring 9 c of the planetary gear set islinked to the carrier of the variator and can be held fixed by firstbrake 28.

FIG. 9 shows the speed diagram of that configuration.

The axis represents the rotation speed of the variator second ringassembly.

As depicted in FIG. 8 a continuously variable mode is used by applyingthe first brake 28, holding fixed the ring 9 c of the planetary gear setas well as the variator carrier 13 c. The power passes through theplanetary carrier 8 c and goes to the first ring assembly 12 c. Therotation speed achievable in CVP mode can be observed as segment 30 onthe speed diagram. The overall ratio is the product of the planetaryratio, the variator ratio and the final drive ratio.

In infinitely variable mode, the second brake 27 is applied, holding thecarrier of the planetary gear set 8 c and the first ring assembly 12 cfixed. The power passes through the ring 9 c of the planetary gear set 5c and goes to the carrier of the variator. In the same manner of theembodiments of FIGS. 4 and 6 this power flow allows for the second ringassembly 11 c to steplessly transition between reverse, neutral andforward speeds, thereby achieving an infinitely variable mode at the CVT3 c output 50 c. This mode provides a reverse function as well as astandstill and a low speed. It can be observed as segment 31 on thespeed diagram. An example motor speed 32 is shown as a reference. Theoverall ratio is the product of the planetary ratio, the variator ratioand the final drive ratio.

The transition between the two modes as embodied in FIG. 8 is done bysimultaneously releasing one of the first and second brakes and applyingthe other of the first and second brakes. This device is able to changecontinuously its ratio to provide the best ratio achievable for theengine in function of the objectives of performance or fuel consumption.In a manual or automatic transmission, only some predetermined anddiscrete ratios are available and an interruption of the powertransmission is needed to shift of ratio. The only interruptions ofpower in this device are the modes shifting.

Example 4

An exemplary embodiment of the invention is shown in FIG. 10 comprisingCVT 3 d. FIG. 8 shows CVT 3 d which may be disposed within a drivelineof a vehicle. The driveline may comprise a motor such as an ICE 100,which may be connected to CVT 3 d via an input shaft ld, and mayoptionally feature a clutch and or damper 2 drivingly engagedtherebetween. The output 50 d of CVT 3 d may be drivingly engaged to avehicle differential and wheels 4. The CVT 3 d of the FIG. 10 embodimentis depicted as comprising: an input shaft ld; a variator 10 d,comprising a first ring assembly 11 d, a second ring assembly 12 d, avariator carrier assembly 13 d, and a set of tilting balls 14 d; aplanetary gear set 5 d comprising a ring gear 9 d, sun gear 6 d, planets7 d and a planetary carrier assembly 8 d; a first brake 33; a secondbrake 34; and the CVT output 50 d. As in the other embodiments the CVToutput 50 d may be coupled to a vehicle differential and wheels (notshown). This configuration uses a planetary gear set and two brakes tohold either the planetary ring gear 9 d or the variator carrier 13 dfixed. The central part of this configuration is the variator 10 d (suchvariators are described previously in the document). A ball ramp 15 d oneach side of the variator provides the clamping force necessary totransfer the torque. Having two brakes, this configuration includes acontinuously variable mode as well as an infinitely variable modeproviding a standstill, reverse and starting function. No startingdevice like a slipping clutch or torque converter is required, since theinfinitely variable mode takes care of the starting function.

The motor 100 (for example an internal combustion engine) is connectedto the 6 d of the planetary gear set via input shaft 1 d. The ring 9 dof the planetary gear set is connected to the first brake 33 and to thefirst ring assembly 11 d. The planetary carrier assembly 8 d is linkedto the carrier of the variator 10 d and can be held fixed by the secondbrake 34.

FIG. 11 shows the speed diagram of that configuration.

The axis represents the rotation speed of the variator second ringassembly.

Continuously variable mode is used by applying the second brake 34,holding fixed the planetary carrier 8 d as well as the variator carrierassembly 13 d. The power passes through the ring gear 9 d and goes tothe first ring assembly 11 d and through the variator 10 d therebyengaging the continuously variable mode. The rotation speed achievablein continuously variable mode can be observed as segment 35 on the speeddiagram. The overall ratio is the product of the planetary ratio, thevariator ratio and the final drive ratio.

In infinitely variable mode, the first brake 33 is applied, holding thering gear 9 d of the planetary gear set and the first ring assembly 11 dfixed. The power passes through the planetary carrier 8 d and goes tothe variator carrier assembly 13 d. As in the embodiments of FIGS. 4, 6and 8 this thereby allows an infinitely variable mode. This modeprovides a reverse function as well as a standstill and a low speed. Itcan be observed as segment 36 on the speed diagram of FIG. 11. Anexample motor speed 37 is shown as a reference. The overall ratio is theproduct of the planetary ratio, the variator ratio and the final driveratio.

The transition between the two modes as embodied in FIG. 10 is done bysimultaneously releasing one of the first and second brakes and applyingthe other of the first and second brakes. This device is able to changecontinuously its ratio to provide the best ratio achievable for theengine in function of the objectives of performance or fuel consumption.In a manual or automatic transmission, only some predetermined anddiscrete ratios are available and an interruption of the powertransmission is needed to shift of ratio. The only interruptions ofpower in this device are the modes shifting.

Example 5

An exemplary embodiment of the invention is shown in FIG. 12 comprisingCVT 3 e. FIG. 10 shows CVT 3 e which may be disposed within a drivelineof a vehicle. The driveline may comprise a motor such as an ICE 100,which may be connected to CVT 3 e via an input shaft le, and mayoptionally feature a clutch and/or damper 2 drivingly engagedtherebetween. The output 50 e of CVT 3 e may be drivingly engaged to avehicle differential and wheels 4. The CVT 3 e of the FIG. 12 embodimentis depicted as comprising: an input shaft le; a variator 10 e,comprising a first ring assembly 11 e, a second ring assembly 12 e, avariator carrier assembly 13 e, and a set of tilting balls 14 e; aplanetary gear set 5 e comprising a ring gear 9 e, sun gear 6 e, planets7 e and a planetary carrier assembly 8 e; a first brake 38; a firstclutch 39; and the CVT output 50 e. The transmission configurationdepicted in FIG. 12 uses a planetary gear set, one brake and one clutch.The central part of that configuration is the variator 10 e describedpreviously herein. A ball ramp 15 e on each side of the variator 10 eprovides the clamping force necessary to transfer the torque. Thisconfiguration includes a continuously variable/infinitely variable modeas well as an infinitely variable mode providing a standstill, reverseand starting function. No starting device like a slipping clutch ortorque converter is required, since the infinitely variable mode takescare of the starting function.

The motor 100, for example an internal combustion engine, is connectedto the sun 6 e of the planetary gear set 5 e. The planetary carrierassembly 8 e is connected to the variator carrier assembly 13 e whilethe ring 9 e of the planetary gear set 5 e is always held fixed. Thefirst ring assembly can be held by the brake 38 or connected to theengine by the clutch 39.

FIG. 13 shows the speed diagram of the configuration of FIG. 12.

The axis represents the rotation speed of the variator second ringassembly.

The infinitely variable/continuously variable mode is used by engagingthe clutch 39, connecting the engine to the first ring assembly 11 e,thus letting the first ring assembly and variator carrier be bothdriven. This infinitely variable/continuously variable mode lies inbetween the infinitely variable mode and the continuously variable modeconcerning speeds. The overall ratio is the product of the sun planetaryratio, the variator ratio and the final drive ratio. The rotation speedachievable in infinitely variable/continuously variable mode can beobserved as segment 41 on the speed diagram.

In infinitely variable mode, the brake 38 is applied, holding the firstring assembly 11 e while the clutch 38 is disengaged. The power passesthrough the planetary carrier assembly 8 e and goes to the variatorcarrier assembly 13 e. As in previously described embodiments drivingthe variator carrier assembly 13 e while holding the first ring assembly11 e allows stepless transitions of the second ring assembly 12 ebetween positive negative and neutral speeds, thereby accomplishing ainfinitely variable mode. This mode provides a reverse function as wellas a standstill and a low speed. It can be observed as segment 42 on thespeed diagram. The overall ratio is the product of the sun planetaryratio, the variator ratio and the final drive ratio.

A gap exists between the infinitely variable mode and infinitelyvariable/continuously variable mode and will be covered by changing theengine speed in order to allow all the vehicle speed.

The transition between the two modes is done by releasing a clutch endengaging the brake to go from the infinitely variable/continuouslyvariable mode to the infinitely variable mode. This device is able tochange continuously its ratio in the infinitely variable and infinitelyvariable/continuously variable modes to provide the best ratioachievable for the engine in function of the objectives of performanceor fuel consumption. In a manual or automatic transmission, only somepredetermined and discrete ratios are available and an interruption ofthe power transmission is needed to shift of ratio. The onlyinterruptions of power in this device are the modes shifting. Anadditional advantage of that configuration is that a small variator canbe chosen.

Embodiments of the variable transmission described herein or that wouldbe obvious to one of skill in the art upon reading the disclosure hereinare contemplated for use in a variety of vehicle drivelines. Fornon-limiting example, the variable transmissions disclosed herein may beused in bicycles, mopeds, scooters, motorcycles, automobiles, electricautomobiles, trucks, sport utility vehicles (SUV's), lawn mowers,tractors, harvesters, agricultural machinery, all terrain vehicles(ATV's), jet skis, personal watercraft vehicles, airplanes, trains,helicopters, buses, forklifts, golf carts, motorships, steam poweredships, submarines, space craft, or other vehicles that employ atransmission.

While the figures and description herein are directed to ball-typevariators (CVTs), alternate embodiments are contemplated another versionof a variator (CVT), such as a Variable-diameter pulley (VDP) or Reevesdrive, a toroidal or roller-based CVT (Extroid CVT), a Magnetic CVT ormCVT, Ratcheting CVT, Hydrostatic CVTs, Naudic Incremental CVT (iCVT),Cone CVTs, Radial roller CVT, Planetary CVT, or any other version CVT.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention. It is intended thatthe following claims define the scope of the invention and that methodsand structures within the scope of these claims and their equivalents becovered thereby.

What is claimed is:
 1. A variable transmission comprising: an inputshaft; a planetary gear set drivingly engaged with the input shaft; afirst brake mechanically coupled to an outer ring gear of the planetarygear set; a variator comprising a variator carrier assembly, a firstring assembly, and a second ring assembly, the variator mechanicallycoupled to a ring gear of the planetary gear set; and a second brakemechanically coupled to a sun gear of the planetary gear set and to afirst ring assembly of the variator a second ring assembly of thevariator drivingly engaged to an output of the variable transmission. 2.The variable transmission of claim 1, comprising a continuously variablemode and an infinitely variable mode.
 3. The variable transmission ofclaim 1, wherein when the first brake is engaged and the second brake isdisengaged, the ring gear of the planetary gear set and a carrier of thevariator are held fixed, thereby engaging a continuously variable mode.4. The variable transmission of claim 2, wherein power passes throughthe sun gear of the planetary gear set to the first ring assembly whenthe transmission is in continuously variable mode.
 5. The variabletransmission of claim 1, wherein when the second brake is engaged andthe first brake is disengaged, the sun gear of the planetary gear setand the first ring assembly are held fixed, thereby engaging aninfinitely variable mode.
 6. The variable transmission of claim 5,wherein power passes through the ring gear of the planetary gear set toa carrier of the variator in the infinitely variable mode.
 7. Thevariable transmission of claim 1, wherein in the infinitely variablemode, the variator provides a reverse function, a standstill functionand a low speed function.
 8. The variable transmission of claim 2,wherein a transition between continuously variable mode and infinitelyvariable mode is accomplished by simultaneously releasing one of thefirst brake and the second brake while applying the other of the firstbrake and the second brake.
 9. The variable transmission of claim 1,wherein the first brake is an electric brake.
 10. The variabletransmission of claim 1, wherein the second brake is an electric brake.